Abstract

A high-velocity radiative shock provides an efficient means to generate
a strong local UV photon field. The optical emission from the shock and
precursor region is then dominated by the photoionized gas, rather than
by the cooling region, and the total optical and UV emission scales as
the mechanical energy flux through the shock. In addition, for
reasonable values of the magnetic field, such shocks become supported by
magnetic pressure in the photoionization/recombination zone of the
shock. The effect of the limited compression factor has a profound
influence on the output spectrum. Models without precursors apply to
unresolved shocks in gas-poor environments or to fast shocks in
individually resolved filaments of supernova remnants. Models with
precursors should be applicable to unresolved structures in gas-rich
environments. In this paper, we present extensive tabular results
designed to be of maximum utility to observationalists for a grid of
low-density steady-flow models covering the shock velocity range 150
<= VS 500 km s-1, and magnetic parameter 0 <=
B/n½ <= 4 muG cm-3/2. In the next paper
of this series, we will apply these models to diagnostic plots for
narrow-line regions of active galactic nuclei.